<template>
    <div class="app-container">
        <!--查询表单-->
        <el-form :inline="true" class="demo-form-inline">

            <!-- 所属分类：级联下拉列表 -->
            <!-- 一级分类 -->
            <el-form-item label="课程类别">
                <el-select v-model="searchObj.subjectParentId" placeholder="请选择" @change="subjectLevelOneChanged">
                    <el-option v-for="subject in subjectNestedList" :key="subject.id" :label="subject.title"
                        :value="subject.id" />
                </el-select>

                <!-- 二级分类 -->
                <el-select v-model="searchObj.subjectId" placeholder="请选择">
                    <el-option v-for="subject in subSubjectList" :key="subject.id" :label="subject.title"
                        :value="subject.id" />
                </el-select>
            </el-form-item>

            <!-- 标题 -->
            <el-form-item>
                <el-input v-model="searchObj.title" placeholder="课程标题" />
            </el-form-item>
            <!-- 讲师 -->
            <el-form-item>
                <el-select v-model="searchObj.teacherId" placeholder="请选择讲师">
                    <el-option v-for="teacher in teacherList" :key="teacher.id" :label="teacher.name"
                        :value="teacher.id" />
                </el-select>
            </el-form-item>

            <!-- <el-form-item>
                <el-select v-model="searchObj.status" clearable placeholder="课程状态">
                    <el-option :value="Normal" label="已发布" :key="Normal" />
                    <el-option :value="Draft" label="未发布" ::key="Draft" />
                </el-select>
            </el-form-item> -->

            <el-button type="primary" icon="el-icon-search" @click="fetchData()">查询</el-button>
            <el-button type="default" @click="resetData()">清空</el-button>
        </el-form>

        <!-- 表格 -->
        <el-table v-loading="listLoading" :data="list" element-loading-text="数据加载中" border fit highlight-current-row
            row-class-name="myClassList">

            <el-table-column label="序号" width="70" align="center">
                <template slot-scope="scope">
                    {{ (page - 1) * limit + scope.$index + 1 }}
                </template>
            </el-table-column>

            <el-table-column label="课程信息" width="470" align="center">
                <template slot-scope="scope">
                    <div class="info">
                        <div class="pic">
                            <img :src="scope.row.cover" alt="scope.row.title" width="150px">
                        </div>
                        <div class="title">
                            <a @click="editChapter(scope.row.id)">{{ scope.row.title }}</a>
                            <p>{{ scope.row.lessonNum }}课时</p>
                        </div>
                    </div>

                </template>
            </el-table-column>

            <el-table-column label="创建时间" align="center">
                <template slot-scope="scope">
                    {{ scope.row.gmtCreate.substr(0, 10) }}
                </template>
            </el-table-column>
            <el-table-column label="发布时间" align="center">
                <template slot-scope="scope">
                    {{ scope.row.gmtModified.substr(0, 10) }}
                </template>
            </el-table-column>
            <el-table-column label="价格" width="100" align="center">
                <template slot-scope="scope">
                    {{ Number(scope.row.price) === 0 ? '免费' :
                            '¥' + scope.row.price.toFixed(2)
                    }}
                </template>
            </el-table-column>
            <el-table-column prop="buyCount" label="付费学员" width="100" align="center">
                <template slot-scope="scope">
                    {{ scope.row.buyCount }}人
                </template>
            </el-table-column>

            <el-table-column label="操作" width="150" align="center">
                <template slot-scope="scope">
                    <span @click="editCourseInfo(scope.row.id)">
                        <el-button type="text" size="mini" icon="el-icon-edit">
                            编辑课程信息
                        </el-button>
                    </span>
                    <span @click="editChapter(scope.row.id)">
                        <el-button type="text" size="mini" icon="el-icon-edit">编辑课程大纲</el-button>
                    </span>
                    <el-button type="text" size="mini" icon="el-icon-delete" @click="deleteCourse(scope.row.id)">删除
                    </el-button>
                </template>
            </el-table-column>
        </el-table>

        <!-- 分页 -->
        <el-pagination :current-page="page" :page-size="limit" :total="total"
            style="padding: 30px 0; text-align: center;" layout="total, prev, pager, next, jumper"
            @current-change="fetchData" />
    </div>
</template>
<script>
import course from '@/api/edu/course'
import teacher from '@/api/edu/teacher'
import subject from '@/api/edu/subject'

export default {

    data() {
        return {
            listLoading: true, // 是否显示loading信息
            list: null, // 数据列表
            total: 0, // 总记录数
            page: 1, // 页码
            limit: 5, // 每页记录数
            searchObj: {
                subjectParentId: '',
                subjectId: '',
                title: '',
                teacherId: '',
                status: '',
            }, // 查询条件
            teacherList: [], // 讲师列表
            subjectNestedList: [], // 一级分类列表
            subSubjectList: [] // 二级分类列表,
        }
    },

    created() { // 当页面加载时获取数据
        this.fetchData()
        // 初始化分类列表
        this.initSubjectList()
        // 获取讲师列表
        this.initTeacherList()
    },

    methods: {
        fetchData(page = 1) { // 调用api层获取数据库中的数据
            // 当点击分页组件的切换按钮的时候，会传输一个当前页码的参数page
            // 解决分页无效问题
            this.page = page
            this.listLoading = true
            course.getPageList(this.page, this.limit, this.searchObj).then(response => {
                // debugger 设置断点调试
                if (response.success === true) {
                    this.list = response.data.rows
                    this.total = response.data.total
                }
                this.listLoading = false
            })
        },
        // 初始化讲师列表
        initTeacherList() {
            course.getListTeacher().then(response => {
                this.teacherList = response.data.items;
            })
        },
        // 初始化分类列表
        initSubjectList() {
            subject.getSubjectList().then(response => {
                this.subjectNestedList = response.data.list;
            })
        },
        // 二级联动
        subjectLevelOneChanged(value) {
            for (let i = 0; i < this.subjectNestedList.length; i++) {
                if (this.subjectNestedList[i].id === value) {
                    this.subSubjectList = this.subjectNestedList[i].children
                    this.searchObj.subjectId = ''
                }
            }
        },

        resetData() {
            this.searchObj = {}
            this.subSubjectList = [] // 二级分类列表
            // 刷新
            this.fetchData()
        },
        // 编辑课程信息
        editCourseInfo(courseId) {
            this.$router.push({ path: '/course/info/' + courseId })
        },
        // 编辑课程大纲
        editChapter(courseId) {
            this.$router.push({ path: '/course/chapter/' + courseId })
        },
        // 删除课程按钮
        deleteCourse(courseId) {
            this.$confirm('此操作将删除课程信息, 是否继续?', '提示', {
                confirmButtonText: '确定',
                cancelButtonText: '取消',
                type: 'warning'
            }).then(() => {
                // 执行.then说明需要删除，后面执行删除代码
                course.deleteCourse(courseId)
                    .then(response => {
                        // 提示信息
                        this.$message({
                            type: 'success',
                            message: '删除成功!'
                        });
                        // 刷新页面
                        this.fetchData();
                    })
            })
        }
    }
}
</script>

<style scoped>
.myClassList .info {
    width: 450px;
    overflow: hidden;
}

.myClassList .info .pic {
    width: 150px;
    height: 90px;
    overflow: hidden;
    float: left;
}

.myClassList .info .pic a {
    display: block;
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
}

.myClassList .info .pic img {
    display: block;
    width: 100%;
}

.myClassList td .info .title {
    width: 280px;
    float: right;
    height: 90px;
}

.myClassList td .info .title a {
    display: block;
    height: 48px;
    line-height: 24px;
    overflow: hidden;
    color: #00baf2;
    margin-bottom: 12px;
}

.myClassList td .info .title p {
    line-height: 20px;
    margin-top: 5px;
    color: #818181;
}
</style>

   
